Labeled side-seamed can body

ABSTRACT

A side-seamed cylindrical metal can body having a nonstretchable, water-resistant, wrinkle-free film label substantially 100 percent bonded thereto is provided wherein the label hides the side seam.

United States Patent 1191 I Kaercher et al. Feb. 4, 1975 [54] LABELED SIDE-SEAMED CAN BODY 2,768,460 10/1956 Northup 40/135 1 1 Ralph William Kwcher, 3523333 2/132? iilii'jjiiiijijiiiiiiii:

Barrington, Stanley Wiswe" 311101554 11/1963 Yazumi Pierce, deceased, late of Lombard. 3,401,475 9/1968 Morehouse et al. 40/300 11]. by Martha Murphy Pierce, executrix Primary Examiner-Robert W. Michell [73] Asslgnee' p g Company Assistant Examiner-Wenceslao J. Contreras reenwlc Attorney, Agent, or Firm-Robert P. Auber; Paul R. [22] Filed: June 26, 1973 Audet; George P. Ziehmer [21] Appl. No.: 373,746

52 u.s. c1. 40/306, 40/135, 40/2 R [57] ABSTRACT 1 [51] InLCl. ..G09f 3/10 A e Seamed C ylrndrlcal metal can body having a [58] F' of Search 252 non-stretchable, water-resistant, wrinkle-free film label substantially 100 percent borrded thereto is pro- References Cited vrded wherem the label h1d-es the side seam. 706 635 UNITED STATES PATENT-S 27 Claims, 5 Drawing Figures 8/1902 Booth 40/306 I LABELED SlDE-SEAMED CAN BODY BACKGROUNDOF THE INVENTION 1 This invention relates to metal can bodies and has particular reference to side-seamed metal can bodies Conventional lithographic processes include cutting I the metal into sheets, applying atleast an inside coating to these sheets and baking. The precoatedshe ets are then printed with metal litho inks, using offset lithogra phy. Such inks are transferred by an offset process to the exterior of the tin'plate sheet. Only one or two colors can be applied per pass of a sheet through such offset lighography equipment, so that, for instance, a'five color label would require three to five passes through the lithography equipment and its attached sheetbaking oven. The final step in the process is the application of a varnish on top of the ink to protect it from scuffing and to provide the can with satisfactory. mobility for subsequent handling. The decorated sheets are then slit into individual body blanks, with care being taken to do the slitting in precise register with the placement of the lithography on the sheet, and this lithography, in turn, in register with the coating outline on the inside of the sheet. With soldered cans, it is also necessary to cut back the lithography from the edges of the body blank which are to be formed into a lock and lap type seam in order that they will not inte rferewith the soldering operation. Thus, when the can has been formed into a body, despite the interfolding of the edges of the body blank there is still approximately three-quarters of an inch of bare, unlithographed metal showing at the side seam area of the container which destroys the continuity of the lithography and makes the appearance of the container less than completely satisfactory. An additional problemstems from what is referred to in the art as the side seam bow which is a direct result of the process, where due to the application'of heat and compressive forces during mechanical forming, the ends of the flat metal sheet which are joined to form the side seam are flattened and distorted resulting in a further unappealing aspect at the side seam. In addition, excess solder is not always vcompletely wiped from the side seam, and the rough, irregular appearance of excess material also contributes to unsightliness. If the solder wiping pressure is 'too great, all of the tin can be removed from parts of the. side seam, and an unsightly dark appearance will'occur.

There are other basic disadvantages of conventional metal lithographic processes that relate to the appearance and performanc'e of the container. First,.offset lithography is limited to screens of a relatively low number of lines, whereas rotogravure printing, used on film labels, can produce finer screen work. Second, in printing individual sheets at relatively high speeds and applying colors one or two at a time, it is difficult to maintain consistent depth or shading of colors or registration between colors so that spoilage increases with the number of colors or trips through the printer. These problems become so severe that six and seven color metal litho labels are virtually unknown in commercial 2 metal containers. .The many handling steps of the metal sheets through many printing presses and wicket ovens tend to bend, dent, or damage the edges of the sheets and further make the can-making process more difficult. Finally, the thin coat of varnish applied over the litho ink is so thin that it is often subject to scratching and damage in both the can-making operation and subsequent handling. In spite of the disadvantages expressed above, ingeneral, metal lithography has become well accepted in the trade, because it is more resistant to damage than its less commonly used alternative, which-is application of a loose, spot-adhered paper label to the can after it has been packed.

The disadvantages of paper labels are obvious. Such labels are easily torn or damaged, are generally hygroscopic, permit easy corrosion of the metal bodies of the containers and can only be applied after the cans have been filled and subjected to sterilization, pasteurization, can warming and other-wet processes, sincesuch treatments usually serve to remove or impair any label applied' prior to such steps.

The film labeling system involved in this invention provides better aesthetics, a greater variety of sub-. strates and decorative effects than can be achieved through conventional metal lithography and presents substantial advantages 'in the quality of printing. First, there is achoice of printing methods, which include rotogravure and flexographic methods in addition to offset printing. The system involves printing continuous webs of film instead of individual sheets which allows the achievement of higher speeds, multiple color application and better registration. A film printing rotogravure line, web fed, for instance, would consist of six or seven color decks, followed by a varnish deck, with drying facilities between each deck in the line. Thus, a seven color label could be printed and varnished in a single pass through such-a line.

A major advantage of film labeling over metal lithography is that it allows a choice between several difficult printing methods depending on the size of 'the job and the quality and number of colors desired. Rotogravure printing allows the-use of finer screens and maintains closer color tolerances, that is, less color variation from image to image, and this technique is highly suitable for long runs. Flexographicprinting does not allow fine screen work but is ideal for short runs. Offset lithography falls somewhat between these extremes.

Today, one of the most important advantages for a film labeling system is the fact that the film label material can be printed in a central location with minimum problems of air pollution from the use of solvents. At the can-making location, the printed film labels are re- Aceived in large rolls, and there 'are no solvent fumes emitted from theentire decorating operation at the can-making plant. This can be contrasted with the need for fume incinerators or other solvent disposal means in connection with the use of metal decorating inks and varnishes at each individual metal can plant for conventional lithography.

The labels themselves can have varnish or plastic film on top of the ink for better scuff resistance, and label changing becomes a much simpler operation wherein it is possible to change one roll of preprinted stock for another in a few minutes without substantially interrupting the production flow in the can line. Label changes are particularly important with carbonated beverages containers, where there are many different flavors, and also in many aerosol product lines.

In view of the above; it is an overall object of this invention to provide a filmla-beling system for decorating side-seamed'metal can bodies that retains the advantages of film labeling, and that is an effective alternative to conventionallithography, including its advantages but not its disadvantages.

In the art of decorating can bodies, the side seam area has presented major problems. One is the unsightliness of the side seams of lithographically decorated cans due to their aforementioned exposed bare metal and grey strip of wiped solder.

7 Efforts to overcome this problem include applying predecorated film labels to the can bodies. This has not heretofore been satisfactory because wrinkles appear in the label adjacent the side seam. Such wrinkles not only are unsightly but they allow moisture to collect in air pockets under the label. This aggravates the unsightliness for example by discoloring the label and causing it to lift off of the can body. This problem is of course acute with paper labels, Attempts to make the labels water resistant by forming them of nonstretchable thermoplastic and other such water resistant materials have not been successful since the wrinkles still occur at the side seam, adhesion there is poor, and lift-off still occurs. Non-stretchable films are desirable since they are dimensionally stable under tensions of web printing and registration cutoff operations. Such films are easier to feed, position for registration to printed indicia, and position for easier cutting prior to being adhered to can body walls.

It has now been discovered that the problem of wrinkling at the side seam is mainly due to irregular physical characteristics of the side seam area. It is not cylindrical like the rest of the can body wall because for example it is circumferentially flattened and is inwardly bowed as it extends axially from top to bottom ends of the can body wall. The significance of the bow, flat and other irregularities such as projections of solder, weld-.

ing flash and side seam cement was not previously recognized. Conventionally, when a film label .is applied to the can body, its leading edge is usually applied to a non-side-seamed wall portion of the can. As the label is progressively wrapped around and eventually'adheringly anchored to the axially straight cylindrical can body wall at the axial edge of the side scam, the label, being axially anchored at the edge of the side seam, cannot stretch and conform to the side seams axially bowed, and circumferentially flattened contour. Usually, only the top and bottom edges of the label are adhered to the top and bottom portions of the can body I wall, which are least bowed. The more axially central portions of the label cannot stretch radially inward to sufficient'ly contact and be permanently adhered to the most aggravated portions of the side seam bow. Labels made with fairly stiff thermoplastic materials desirable for scuff resistance such as polyethylene terephthalate and vinylidenechloride polymer-coated cellophanes and otherstiff labels such as those containing paper and/or foil, tend to spring back when forced radially inward to the contour of the side seam bow. Such labels are difficult to adhere to the contours of side seam bows especially in high speed can manufacturing lines. Resulting 'poor adhesion, wrinkles, air pockets, etc. at the side seam precluded application of such labels to can bodies for example, to cans of pressurized products 4 such as aerosol, beer and carbonated beverages, until after such cans were filled and immersed in water baths. I-Ieretofore, there has been no known commercial-or other instance wherein a sideseamed can body could be labeled before it was subjected to water baths such as exacting aerosol water bath tests of 160 F for 5 minutes, pasteurization baths of 140 F for 20V minutes, or pre-sterilized beer and soft drink can warming baths of F for 5 minutes.

It has been found that the aforementioned problems are overcome and side-seamed can bodies with labels substantially percent bonded thereto and wrinklefree adjacent their side seam areas, can be provided when the leading edge of the label is placed within the side seam area bows or flattened surface area and the trailing edge is lapped thereover with the overlapped portions of the label being in and hiding the side seam area of the can body wall.

Accordingly, it is a primary object of this invention to provide a side-seamed metal can body having a wrinkle-free' film label substantiallyIlOO percent bonded thereto.

' Another primary object of this invention is to provide a labeled side-seamed metal can body wherein the label is wrinkle-free at the side seam area.

Another primary object of this invention is to provide the aforementioned labeled can body wherein the label hides the side seam area.

Another object of this invention is to provide the aforementioned labeled can body wherein the sideseam is soldered and the label overlap. hides the solder on the exterior of the side seam area.

, Another object of this invention is to provide the aforementioned labeled can body wherein the label overlap hides the irregular physical characteristics at the side seam.

Another object of this invention is to provide a sideseamed can body having a hon-stretchable waterresistant, wrinkle-free side seam-hidingfilm label substantially 100 percent bonded thereto. I

Anotherobject of this invention to provide a sideseamed metal'can body having anon-stretchable waterresistant, wrinkle-free side seam-hiding film labelv substantially 100 percent bonded thereto, wherein the labeled can body has the ability to withstand a water bath test of F for 5 minutes.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side view of an embodiment of a labeled metal can body of this invention. I

FIG. 2 is an enlarged section taken substantially along line 2-2 of. FIG. I.

FIG. 3 is an enlarged fragmentary section taken through a length of can body wall substantially along line 3-3 of FIG. 2.

FIG. 4 is an enlarged fragmentary section as would be taken through the wall of another .embodiment of the can body of this invention. FIG. 5 is a schematic view showing the method, of forming the labeled metal can body of this invention.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawing in detail, FIG. 1 is a labeled,

I empty, open-ended, cylindrical, side-seamed, flanged,

metal can body, generally designated 10, having end closure 12 secured to the bottom of can body 14, as by a conventional double seam 16 (FIG. 3), having a flange 17 at the upper open end, and having film label, generally designated 18, adhered to substantially the entire circumference of can body wall 15. Film label 18 has a leading edge 20 positioned parallel to the central axis of can body 14 and to side seam juncture generally designated 24 (FIG. 2) of a side seam generally designated 26. Label 18 also has a trailing edge 28 and an adjacent trailing marginal edge portion 30 which overlaps and is adhered to underlying leading marginal edge portion 22 (FIG. 2).

FIG. 2 is an enlarged section taken substantially along line 2-2 of FIG. 1 and shows a portion of locked side seam 26 secured by means of solder 28. Label 18 is adhered to substantially the entire exterior surface of the body wall by adhesive 34 which also secures trailing marginal edge-portion 30 to underlying leading marginal edge portion 22. FIG 2 shows that wall 15 of can body 14 is not perfectly cylindrical since for one thing, it has a generally flattened surface area 33 within side seam area generally designated 32. For purposes of this invention, the side seam area, here 32, is that portion of the exterior surface of a can body wall that is within about /2 inch to either side of the side seam juncture, here generally designated 24 and particularly designated 36. The sideseam area is intended to include within its bounds or margins any solder, weld flash, cement or other side-seaming, joining, working and treating materials which occur as physical irregularities such as projections on the wall surface,any side seaming, joining or working effects such as junctions and indentations,or any such or other unsightlinesses such as discolorations, e.g. the strip of wipedsolder adjacent soldered side seams. The side seam area includes within its bounds, the side seam bow, if any, defined as that portion of the can body wall within the side seam area, that is radially inwardly bowed substantially from top to bottom ends of the canbody wall- ,-the flattened wall surface area or areas, if any, which run alongside the side seam juncture and, such as herein depicted, the flattened surface 33 extends circumferentially from adjacent one side of side seam 26 to adjacent the other, i.e., from adjacent the rounded end of U-shaped inner fold 35 to adjacent section line 3-3 to the right of side seam juncture 36,the side seam itself, defined as the joined, overlapped or-folded portions of the can body wall,and the side seam juncture, generally defined as and usually being an axial line formed on the exterior surface of the can body wall where opposing wall portions meet, and more particularly defined as the exterior fold, here 36, of locked wall portions of locked and of locked and lapped side seams, and as the exterior edge of the overlap for lapped and scived side seams. In FIG. 2, the overlapped marginal edge portions 'of label 18 cover the side seam area 32, flattened surface area 33, and for example any strip of wiped side seam solder or other physical irregularities that appear therein.

FIG. 3 is an enlarged fragmentary view taken axially through body wall 15 substantially along line 33 of FIG. 2. More particularly, FIG. 3 shows thatlabeled can body 10, is radially inwardly bowed from top to bottom ends of body wall 15. FIG. 3 also shows end'closure 12 secured to container body wall 15 by double seam l6 and showscross sections of trailing marginal edge portion 30 and of leading marginal edge portion 22. Label 18 comprises a base layer and an adhesive layer 34 which adheres the label to body wall 15. The

' particular embodiment of label 18 -shown, is anonstretchable, water-resistant baselayer of polyethylene terephthalate and adhesive 34 is a quick-tack hot-melt selected from the group consisting of awax material and an ethylenic acidic polymer.

FIG. 4 is an enlarged fragmentary section as would be taken through another embodiment of the labeled can body of this invention. FIG. 4 shows alabeled can body 14', its metal body wall 15' having a label, generally designated 18' bondedthereto by adhesive 34'. In this embodiment, label 18 comprises a base layer compos-.

ite of 'a vinylidene chloride-coated cellophane VCC, overcoated with polypropylene PP.

FIG. 5 is a schematicview showing basic steps involved in the method of forming the labeled, cylindrical, side-seamed, metal can body of this invention.

In the usual manner of forming an empty side-seamedcylindrical metal can body having a locked side seam, a conventional body maker machine forms hooks on two ends of the body, b'endsthe body about the mandrel, interlocks the hooks and bumps or presses them tight into a locked seam. The formed and locked can body is then conveyed over a roll revolving in a pot of molten solder which applies solder to the locked seam. The locked seam remains in contact with the roll until the seam is brought up to a temperature beyond the melting point of the solder, and excess solder is brushed or wiped off along the length of the side seam. This leaves a grey unsightly strip of wipedsolder on the external wall of the can body which is then sometimes sprayed with an organic coating to protect the solder for example from being rubbed offon rails during the rest of the can manufacturing operation. It is this heat and bumping action which causes the side seam area to bow radially inwardly and to be flattened axially from top to bottom ends of the can body wall.

Interior and/or exterior surfaces of the flanged or unflanged can bodies need not but can be coated and the coatings baked although any coating thereof must be effected before labeling since temperatures employed for curing the coating greatly exceed the tackifying temperature range of the adhesive and would impair adherence of the'label to the can body wall. Commonly, formed and seamed can bodies are flanged just after they leave a body maker machine and their interior surfaces are spray-coated with product-protective organic materials and cured in ovens heated to about 400 F and higher.

The flanged and coated can body is then heated to a temperature within the tackifying temperature range of the quick-tack, hot-melt adhesive on the undersurface of the base layer of the label. Heating the can body activates the adhesive on the label so that the labeladheres to the can body when they are brought into contact with each other. ,The tackifying temperature range may vary with the adhesive. For example, the range of the ethylenic acidic polymer adhesive is from about 185 to 250 F while that of a wax material such as the hereinbefore described wax-mixture material is from about l-210 F. Generally speaking, the lower temperature value of the range must be high enough to obtain good substantially 10,0 percent adhesion in the time allowed, andthe higher temperature of the range must be low enough that the adhesive is not too fluid or soft and causes skating, or separation or unraveling of the overlap, also in the time allowed. When the time allowed is very short, usually substantially less than l second for high speed can lines, besides heating the can body, it sometimes is advantageous to also heat the adhesive on at least one or both marginal edge portions of the label, to the tackifying range of the adhesive, prior to or as the label is being applied to the heated can body. Heating the marginal end portions is advantageous when short dwell times do not allow enought time for can heat to penetrate the underlying leading marginal edge portion of the label and activate the adhesive on the overlapping marginal edge portion of the overlap.

The step'of heating the can body for labeling can be effected by curing ovens during the curing step, or if curing heat is not employed, any conventional heating means such as a separate recirculating hot air oven can be employed. Heating of marginal edge portions of labels during high speed can manufacturing lines can be effected by any suitable means such as a closely applied gas burner.

The heated, or unheated, film'label, which is bonded to substantially the entire circumference of the'heated can body can be supplied from any source, preferably from a roll or web, and when applied, is cut toa dimension that provides it'with leading and trailing edgesand allows it to cover the exterior can body wall surface within say about 1/64 inch to 1/32 inch of its top and/or bottom ends for cans with assembled end closures, such as aerosol cans andwithin about 1/32 inch from start of each flange radius for openended cans.

in accordance with this invention, the film label is adhered to the canibody by positioning and adhering'the leading edge of the label parallel to the central axis of,-

and within the side seamarea 32 of the can body wall.

The side seam area as previously defined extends circumferentially about /2 inch to either side of the side seam juncture. The trailing marginal edge portion of.

the label can be lapped over and adhered to the underlying marginal edge portion ofthe leading edge so that the overlap is within the side seam area. The leading edge can also be positioned and adhered adjacent one margin of the side seam area, and the overlap can cover at least the side seam juncture, and sometimes, more desirably it covers a substantial portion of or it coincides with and covers the entire side seam area. When the side seam area includes a side seam bow and/or flattened surface. area, the leading edge should be positioned and adhered there within. Although the bow and flattened surface ofmost side seams usually only' extend from A to /2 inch to either side of the juncture, they may extend further, and it is to be noted that this invention encompasses such situations. The aforementioned positioning and adhering of the leading edge of the label not only meets a primary objective of the invention by providing a label that is wrinkle-free at the side seam, but-allows another primary objective to be attained, that of hiding the hereinbefore mentioned side seam irregularities and unsightlinesses not only with opaque materials but also even withv transparent I films, by treating their overlapping marginal edge portions as by pigmenting the labels and/or by placing printing matter on their surfaces. For economic reasons and/or when total hiding of the side seam area is not necessary, the length of the overlap in the side seam area can be kept to a minimum that will obtain the adhesion and water resistance desired, usually the minimum overlap is about 3/16 to inch.

Though it is preferred to position the entire overlap within the side seam area, some overlap beyond the 8 side seam area is tolerable when it does not unduly impair adhesion or cause wrinkles.

it has been found that positioning and adhering the leading edge of the label'within the side seam area according to this invention is the only way that substantially 100 percent bonded non-stretchable film labels can be applied to metal can bodies with irregularly contoured side seams without having wrinkles in the label at the side seam area. Starting with the leading edge in the side seam bow allows the label to bend and conform to the contour of the bow because no other portion of the non-stretchable label is already anchored to the can body.-Contrastingly, conventionally, when the leading edge of such a label is applied to another portion of the can body and the label is progressively wrapped around and eventually adheringly anchored to the axially straight cylindrical can body wall at the axial edge of the side seam, the label, being axially anchored at the edge of the side seam, cannot stretch and conform to for example the inwardly bowed and/or circumferentially flattened surface area of the can body wall. Usually, only the top and bottom edges of the label are adhered to the least bowed top and bottom portions of the can 'body wall, but the more axially central portions of the label cannot stretch inward sufficiently to contact and be permanently adhered to the most aggravated portions of the side seam bow. Labels made of fairly stiff materials desirable for example for scuff resistance such as polyethylene terephthalate tend to spring back when forced radially inwardto the contour of the side seam bow. Such labels are especially difficult to adhere to side seam bows in high speed short dwell times. Such inadequate adhesion'at the side seam area causes air bubbles and pockets which collect water during water bath' tests, such as for aerosol cans, and lift the label from the can and otherwise destroy its aesthetic qualities.

Once having positioned and adhered the leading edge of the label as desired within the side seam area, the adhesive side of the label is wrapped around and progressively adhered to substantially the entire circumference of the can body, and the trailing marginal edge portion of the label is lapped over and adhered'to an underlying leading marginal'edge portion in one of the aforementioned manners.

In applying the label to the heated can body, it, has been found advantageous to employ means such as a pad or roller which provides sufficient resiliency and pressure to adhere substantially the entire marginal edge portions of the label to each'other and to for example the bowed, flattened wall portions of the side seam area.

In the method of this invention, the can bodies may but need not have an end closure secured to one or both of their ends. End closures can be secured to the tus disclosed in US. Pat. application Ser. No. 318,887,

filed on Dec. 27, 1972, and assigned to the assignee of the subject invention. The apparatus therein disclosed orients can bodies by subjecting them to a pressurized fluid such as air at a volume sufficient'to buoy the bodies and for a time sufficient to allow gravity to orient ylene, polypropylene, anda rapid-curing oleoresinous coating. The polyethylenes preferably are of a high density. The base layer includes at least one nonstretchable material such as polyethyleneterephthalate or a polymer-coated cellophane. Though such materials, especially thin layers thereof, are inherently stretchable to some small extent, non-stretchable here means essentially non-stretchable, is that they will not stretch enough naturally and without being specially oriented to conform and be adhered to the bow of the side seam without wrinkling. A suitable polyethylene terephthalate is sold under the trade designation Mylar, a desirable vinylidene chloride polymer-coated cello phane commonly known as Saran-coated cellophane, is sold under the trade designation K-Cello, both materials being manufactured by E. l. DuPont de Nemours & Company.

The rapid-curing oleoresinous coating can be any of the suitable thermosetting varnishes such as alkyd resin materials which are reaction products of (1) oils, such as linseed, soybean, coconut, castor, cottonseed, etc., or oils of converted fatty acids, and phthalic anhydrides modified by melamine or urea formaldehyde resins and dissolved in organic solvents. The coatings are usually activated by acid catalysts to decrease curing times. Examples of commercially available curing-type alkyd resins are sold under the trade designation Sparkle'nes, manufactured by Morton chemical Company, and

Crystophanes, manufactured by lnmont Corporation.

The wax material can be any suitable waxed-based adhesive. Preferably, it comprises about 35 percent by weight of a petroleum wax preferably an intermediate grade, about 40 percent by weight ethylene-vinyl acetate copolymer and about 25 percent by weight of a mixture of ethylene-vinyl acetate copolymer, terpene tackifier and rosin ester resin. The preferred tackifying range of this wax material is from about l952l0 F.

The ethylenic acidic polymer adhesive includes ethylene acrylic acid copolymers believed disclosed in US. Pat. No. 3,239,370 assigned to The Dow Chemical Company, and zinc-neutralized ionic copolymers of ethylene and a,B-ethy1enically unsaturated carboxylic acids, commonly known'and sold under the trademark Surlyn" by E. l. Dupont de Nemours & Company. Methods of preparing surlyn ionic copolymer and their properties are believed disclosed in US. Pat. No. 3,264,272, filed on Apr.8, 1963 andassigned to Du- Pont. The tackifying range of the ethylenic acidic polymer adhesives is believed to be from about 185 to 250 F. For high speed can manufacturing and labeling lines wherein labels are applied to cans in less than one second at from about 175 to as high as 800 cans per minute, the adhesive must adhere without slippage to the heated can body in the aforementioned less than 1 second. As will be explained, labels applied to cans used for packaging aerosol products, beer and carbonated beverages, must be sufficiently moisture or water resistant to maintain their adhesion to can bodies at temperatures ranging for example for aerosol cans up to about 160 F. The adhesives can be applied to-the base layer of the film label in any conventional manner. 5 The wax materials can for example be applied in liquid form to patterned rotogravure cylinders which are then rolled against smoothing bars for application of the wax as a smooth layer to the base layer. The ethylenic acidic polymer adhesives can be extruded on the base layer material. When the label comprises polymer-coated cellophane and an overcoat, the adhesive employed must be compatible with the overcoat to provide proper adhesion at the labeloverlap.

Base layers of this invention which are opaque or pigmented can be printed on their upper surfaces, and clear layers such as polyethylene terephthalate can be reverse printed on their under surfaces for example to obtain maximum scuff protection. Although any suitable conventional printing ink can be employed, the inks must be compatible with their substrates and adjacent materials, and must not impair adhesion of the label to the can body or to itself at the overlap. it is often desirable to provide non-printed areas in clear 25 films to allow show-through of bright shiny body wall surfaces areas.

The overall thickness of the film label of this invention can be any suitable thickness and it need not be but generally is less than about .0035 inch, preferably less than about .00325 inch thick. Satisfactory results can be obtained with a label whose adhesive layer is about .001 inch and whose base layer of polyethylene teraphthalate is about .0005 inch thick. Satisfactory results are also obtainable with a label whose adhesive layer is about .0012 inch thick and whose base layer composite is the polymercoated cellophane layer about .00125 inch thick and the overcoat is polypropylene of about .00075 inch thick.

The empty cylindrical metal can body of this invention to which the film label is bonded can be any metal side-seamed can body having the here'inbefore described and defined side seam areas which would cause a non-stretchable label to wrinkle at the side seam area. Cylindrical here means essentiallycylindrical, since for example the bow and flat are non-cylindrical.

The labeled metal can' body of this invention has exceptional water resistance due to the combination of the water resistance of the exterior layer of polyethylene terephthalate, the overcoat, the vinylidene polymer-coated cellophane, and the wax and ethylenic acidic polymer adhesives, plus the wrinkle-free 360 bond achieved by placing the leading edge of the label and the overlap within the side seam area.-

The excellent water resistance of the labeled can bodies of this invention is demonstrated by their ability to withstand various heated water bath tests. This renders the labeled can bodies especially suitable for packaging aerosol products and carbonated beverages such as beer and carbonated beverages since the bodies when filled and secured, in the former instance, can withstand the 5 minute 160 F water bath needed to bring aerosol contents up to 130 F as federally required to identify leakers and potentially explosure containers. In the latter instance, they withstand-the 140 F, 20 minute beer pasturization water bath test, and the 90 F 5 minute pre-sterilized beer and soft drink can warming test.

' carboxylic acid.

his thought that the invention and many of its attendant advantages willbe understood from the foregoing description and it will be apparent that various changes may be made in the, form, construction and arrangement of the-parts without'departing from the spirit and a non-stretchable, wrinkle-free, water-resistant film label bonded to substantiall'y the entire circumference of the can body wall by a quick-tack hot-melt adhesive, the label-beingcomprisedof a base layer and an adhesive layer, the ,base layer-being selected "from the group consisting. of polyethylene terephthalate, and a composite of (l) a vinylidene chloride polymer-coated cellophane and(2) a water-resistant overcoat selected from the group consisting of polyethylene, polypropylene and a rapidcuring oleoresinousmaterial, the adhesive being selected from the group consisting of a wax material and an ethylenic acidic polymer, the label having a leading edge and a trailing edge, the leading edge being positioned parallel to the central axis of the can body within the side seam area and the trailing marginal edge portion being lapped over and adhered to the underlying marginal edge portion of the leading edge so that the overlap is within the side seam 'area.

2. The labeled can body of claim 1 wherein the overlaphides the side seam area.

3. The labeled can body of claim 2 wherein the side seam area also includes projections of side-seam joining material on the exterior surface of the can body.

' wall. 4. The labeled can body of claim 1 wherein the side seam is soldered, the, side seam area includes a strip of wiped solder, and the overlapped marginal edge portions of the label are pigmented and hide the strip of wiped solder.

5. The labeled can body of claim 4 whereinthe wax material adhesive comprises about 35 percent by mer, terpene resin tackifier and rosin ester resin.

6. The labeled container of claim 4 wherein the ethylenic acidic polymer is a zinc-neutralized ionic copoly- 10. A cylindrical side-seamed metal can body having a wrinkle-free water-resistant film label bonded to substantially the entire circumference of the can body wall, which comprises:

a cylindrical side-seamed metal can body, the side seam area of the can body wall having an exterior surface which includes an inward bow and a side seam juncture within the bow, and

a non-stretchable, wrinkle-free, water-resistant, film label bonded to substantially the entire circumference of the can body wall by a quick-tack hot-melt adhesive, the label being comprised of a base layer and an adhesive layer, the base layer being selected from the I group consisting of polyethylene terephthalate, and a composite of l) vinylidene chloride polymer-coated cellophane and (2) an 'overcoat selected from the group-consisting of a rapidcuring oleoresinous coating, the adhesive being selected from the group consisting of a wax material and an ethylenic acidic polymer, the label having a leading edge and a trailing edge, the leading edge being positioned parallel to the central axis of the can body within the side seam bow and the trailing marginal edge portion being lapped over. and adhered to the underlying marginal edge portion of the leading edge so that the trailing edge is also par- I allel to the central axis and is within the side seam bow.

11. The labeled can body of claim 10 wherein the overlap hides the side seam area within the side seam bow. I

12. The labeled can body of claim 11 wherein the overlapped marginal edge portions are opaque.

13. The labeled can body of claim 11 wherein the can body is empty and its top and bottom ends are flanged.

14. The labeled can body of claim 13 wherein the can body is for packaging carbonated beverages.

15. The labeled can body of claim .13 wherein the can .body is for packaging beer.

16. The labeled can body of claim 13 wherein the can body is for packaging aerosol products. 4

17. The labelled can body of claim 16 wherein the overall thickness of the label is less than about .0035 inch and wherein the wax adhesive has a tackifying temperature range of about l95-2l0 F and comprises from about 35 percent by weight petroleum wax, about 40 percent by weight ethylene vinyl acetate copolymer, and about 25 percent by weight of a mixture of ethylene vinyl acetate copolymer, terepene resin tackifier and rosin ester. resin, the label being one which will maintain its adherence to the can body when the lab'eled can body is subjected to a water bath of about 160 F for about 5 minutes.

mer of ethylene and an a,B-ethylenically unsaturated 9. The labeled can body of claim 1 wherein the overall thickness of the film label is no greater than about .0035 inch. v

18. The labeled can body of claim 1 1 wherein the can body is empty, it is for aerosol products and its top and bottom ends have end closures secured thereto.

19. The labeled can body of claim 10 wherein the side seam is soldered, the side seam area includes a strip of wiped solder within the bow and the overlapped marginal edge portions hide the strip of wiped'solder. 20. The labeled can body of claim 19 wherein the label is substantially transparent and the overlapped marginal edge portions are pigmented sothat the pigmentation and the double thickness of the overlap cooperate'to hide the strip of wiped solder.

21. The labeled can body of claim 20 wherein the overlapped marginal edge portions also have a printed matter thereon which aids in hiding the strip of wiped solder.

22. The labeled can body of claim 19 wherein the wax material adhesive has a tackifying temperature range of about l95 2l0 F and comprises from about 35 percent by weight petroleum wax, about 40 percent by weight ethylene vinyl acetate copolymer, and about 25 percent by weight of a mixture of ethylene vinyl acetate copolymer, terpene resin tackifier and rosin ester resin.

23. The labelled can body of claim 22 wherein the ethylenic acidic copolymer is a zinc ionized copolymer of ethylene and an a,B-ethylenically unsaturated carboxylic acid.

24. The labelled can body of claim 23 wherein the overall thickness of the film label is .0035 inch.

25. The labeled can body of claim 10 wherein the leading edge of the label is positioned adjacent one margin of the side seam bow, and the overlap covers and hides the side seam juncture.

26. The labeled container of claim 25 wherein the overlap coincides with the area of the side seam bow.

27. An empty cylindrical side-seamed metal can body having end closures secured thereto and having a wrinkle-free water-resistant film label bonded to substantially the entire circumference of the can body wall, which comprises:

seam area of the can body wall havingan exterior surface which includes a side'seam juncture, a flat-" tened surface area, a strip of wiped solder, and a radially inward bow, and

non-stretchable, wrinkle-free, water-resistant, film label bonded to substantially the entire circumference of the can body wall by a quick-tack hot-melt adhesive, the label being comprised of a base layer and an adhesive layer, the base layer of a composite of l a vinylidene chloride polymer-coated cellophane top-printed and overcoated with polypropylene, and the adhesivebeing selected from the group consisting of a wax material and an ethylenic acidic polymer, the label having a leading edge and a trailing edge, the leading edge being positioned paralled to the central axis of the container body and within the side seam area, so that its marginal edge portion helps cover the strip of wiped solder, and the trailing edge is also parallel to the central axis of the can body and within the side seam area, and its marginal edge portion helps cover the strip of wiped solder by overlapping and being adhered to the underlying marginal edge portion of the leading edge, so that the overlapped marginal edge portions together hide the strip of wiped solder. 

2. The labeled can body of claim 1 wherein the overlap hides the side seam area.
 3. The labeled can body of claim 2 wherein the side seam area also includes projections of side-seam joining material on the exterior surface of the can body wall.
 4. The labeled can body of claim 1 wherein the side seam is soldered, the side seam area includes a strip of wiped solder, and the overlapped marginal edge portions of the label are pigmented and hide the strip of wiped solder.
 5. The labeled can body of claim 4 wherein the wax material adhesive comprises about 35 percent by weight petroleum wax about 40 percent by weight ethylene-vinyl acetate copolymer, and about 25 percent by weight of a mixture of ethylene-vinyl acetate copolymer, terpene resin tackifier and rosin ester resin.
 6. The labeled container of claim 4 wherein the ethylenic acidic polymer is a zinc-neutralized ionic copolymer of ethylene and an Alpha ,B-ethylenically unsaturated carboxylic acid.
 7. The labeled container of claim 6 wherein the overlap coincides with the side seam area.
 8. The labeled can body of claim 1 wherein the leading edge of the label is positioned adjacent one margin of the side seam area, and the overlap covers and hides the side seam juncture.
 9. The labeled can body of claim 1 wherein the overall thickness of the film label is no greater than about .0035 inch.
 10. A cylindrical side-seamed metal can body having a wrinkle-free water-resistant film label bonded to substantially the entire circumference of the can body wall, which comprises: a cylindrical side-seamed metal can body, the side seam area of the can body wall having an exterior surface which includes an inward bow and a side seam juncture within the bow, and a non-stretchable, wrinkle-free, water-resistant, film label bonded to substantially the entire circumference of the can bodY wall by a quick-tack hot-melt adhesive, the label being comprised of a base layer and an adhesive layer, the base layer being selected from the group consisting of polyethylene terephthalate, and a composite of (1) vinylidene chloride polymer-coated cellophane and (2) an overcoat selected from the group consisting of a rapid-curing oleoresinous coating, the adhesive being selected from the group consisting of a wax material and an ethylenic acidic polymer, the label having a leading edge and a trailing edge, the leading edge being positioned parallel to the central axis of the can body within the side seam bow and the trailing marginal edge portion being lapped over and adhered to the underlying marginal edge portion of the leading edge so that the trailing edge is also parallel to the central axis and is within the side seam bow.
 11. The labeled can body of claim 10 wherein the overlap hides the side seam area within the side seam bow.
 12. The labeled can body of claim 11 wherein the overlapped marginal edge portions are opaque.
 13. The labeled can body of claim 11 wherein the can body is empty and its top and bottom ends are flanged.
 14. The labeled can body of claim 13 wherein the can body is for packaging carbonated beverages.
 15. The labeled can body of claim 13 wherein the can body is for packaging beer.
 16. The labeled can body of claim 13 wherein the can body is for packaging aerosol products.
 17. The labelled can body of claim 16 wherein the overall thickness of the label is less than about .0035 inch and wherein the wax adhesive has a tackifying temperature range of about 195*-210* F and comprises from about 35 percent by weight petroleum wax, about 40 percent by weight ethylene vinyl acetate copolymer, and about 25 percent by weight of a mixture of ethylene vinyl acetate copolymer, terepene resin tackifier and rosin ester resin, the label being one which will maintain its adherence to the can body when the labeled can body is subjected to a water bath of about 160* F for about 5 minutes.
 18. The labeled can body of claim 11 wherein the can body is empty, it is for aerosol products and its top and bottom ends have end closures secured thereto.
 19. The labeled can body of claim 10 wherein the side seam is soldered, the side seam area includes a strip of wiped solder within the bow and the overlapped marginal edge portions hide the strip of wiped solder.
 20. The labeled can body of claim 19 wherein the label is substantially transparent and the overlapped marginal edge portions are pigmented so that the pigmentation and the double thickness of the overlap cooperate to hide the strip of wiped solder.
 21. The labeled can body of claim 20 wherein the overlapped marginal edge portions also have a printed matter thereon which aids in hiding the strip of wiped solder.
 22. The labeled can body of claim 19 wherein the wax material adhesive has a tackifying temperature range of about 195*-210* F and comprises from about 35 percent by weight petroleum wax, about 40 percent by weight ethylene vinyl acetate copolymer, and about 25 percent by weight of a mixture of ethylene vinyl acetate copolymer, terpene resin tackifier and rosin ester resin.
 23. The labelled can body of claim 22 wherein the ethylenic acidic copolymer is a zinc ionized copolymer of ethylene and an Alpha ,B-ethylenically unsaturated carboxylic acid.
 24. The labelled can body of claim 23 wherein the overall thickness of the film label is .0035 inch.
 25. The labeled can body of claim 10 wherein the leading edge of the label is positioned adjacent one margin of the side seam bow, and the overlap covers and hides the side seam juncture.
 26. The labeled container of claim 25 wherein the overlap coincides with the area of the side seam bow.
 27. An empty cylindrical side-seamed metal can body having end closures secured thereto and having a wrinkle-freE water-resistant film label bonded to substantially the entire circumference of the can body wall, which comprises: a cylindrical side-seamed metal can body, the side seam area of the can body wall having an exterior surface which includes a side seam juncture, a flattened surface area, a strip of wiped solder, and a radially inward bow, and a non-stretchable, wrinkle-free, water-resistant, film label bonded to substantially the entire circumference of the can body wall by a quick-tack hot-melt adhesive, the label being comprised of a base layer and an adhesive layer, the base layer of a composite of (1) a vinylidene chloride polymer-coated cellophane top-printed and overcoated with polypropylene, and the adhesive being selected from the group consisting of a wax material and an ethylenic acidic polymer, the label having a leading edge and a trailing edge, the leading edge being positioned paralled to the central axis of the container body and within the side seam area, so that its marginal edge portion helps cover the strip of wiped solder, and the trailing edge is also parallel to the central axis of the can body and within the side seam area, and its marginal edge portion helps cover the strip of wiped solder by overlapping and being adhered to the underlying marginal edge portion of the leading edge, so that the overlapped marginal edge portions together hide the strip of wiped solder. 